1. Field of the Invention
This invention relates to a material handling apparatus and more particularly to material handling apparatus that includes a scraper bowl that is connected to a conveyor system that is movable with the scraper bowl to provide continuous loading, transporting and unloading of the material.
2. Description of the Prior Art
Conventional earth moving and excavation machines that include a scraper bowl propelled by a prime mover load material, such as earth, into the scraper bowl as the prime mover advances the scraper blade in contact with the material. Once the scraper bowl is loaded, it must be removed from the loading cycle by transporting the scraper bowl to a location distant from the work site for unloading.
Consequently, the efficiency of the scraper bowl is substantially reduced by removing the scraper bowl from the loading operation as it is being transported and unloaded. Thus, if the earth moving machine is to be operated substantially continuously, it is necessary to maintain the earth moving machine in the loading cycle and avoid intermittent shut-downs of the loading cycle during the transporting and unloading of the earth moving machine.
One device for continuously handling material without interrupting the loading cycle is disclosed in U.S. Pat. No. 1,241,880 wherein a stone gathering device is carried forwardly of a mobile support frame and is adapted to gather up stones on the ground and transfer them onto an inclined endless conveyor that is supported rearwardly of the gathering device on the mobile frame. The discharging end portion of the endless conveyor is elevated in overlying relationship above an inclined transverse conveyor that has a discharging end portion arranged in overlying material receiving relationship with a wagon to be loaded with the gathered stones. With this arrangement, the wagon may travel with the gathering machine to permit continuous gathering of the stones simultaneous with loading the stones into the wagon. One disadvantage of this system is that the gathering and conveying of the material must be terminated during the period in which an unloaded wagon replaces a loaded wagon in material receiving relationship with the transverse conveyor.
In U.S. Pat. No. 3,507,060, a conventional motor scraper is provided with an elevator positioned in the scraper bowl and arranged in material discharging relationship with a side casting conveyor. The earthen material loaded into the scraper bowl is conveyed by the elevator conveyor into the side casting conveyor that includes a hopper for intermittent storage of the earthen material. With this arrangement, the side casting conveyor is adapted to unload the material into a haulage vehicle as the material is loaded in the scraper bowl. During the period of time in which the haulage vehicle is removed from material receiving relationship with the side casting conveyor, the material may be intermittently stored within the hopper of the side casting conveyor. Upon return of the haulage vehicle in material receiving relationship with the side casting conveyor, the conveyor motor thereof is actuated to continue the unloading of the material from the scraper bowl.
A system employing a pivotal discharge conveyor wherein continuous excavation of material by a conventional front end loader is sought to be effected is disclosed in U.S. Pat. No. 3,680,233. In this system, an elevator is mounted to the front end portion of the loader and is adapted to receive material picked up by the scraper blade. The material is transferred from the elevator by an interconnecting conveyor onto a rear mounted swivel conveyor. The rear mounted swivel conveyor is arranged to swing by operation of a hydraulic cylinder about a horizontal axis in vertical arcs. Material is discharged from the swivel conveyor into a conventional hauling vehicle located to either side of the continuous excavating vehicle. The hauling vehicle proceeds at the rate of speed of the continuous excavating vehicle as it is being loaded; however, the loading operation must be interrupted during the exchange of an unloaded hauling vehicle with a loaded hauling vehicle in material receiving relationship with the swivel conveyor.
There is need for an apparatus for the hauling of earthen material which continuously loads and transports the earthen material without interruption during the unloading of the earthen material.